docs: def split(src, chunksize=MINWEIGHT):
      """
      Split a complex fault source in chunks
      """
      for i, block in enumerate(block_splitter(src.iter_ruptures(), chunksize,
                                               key=operator.attrgetter('mag'))):
          rup = block[0]
          source_id = '%s:%d' % (src.source_id, i)
          amfd = mfd.ArbitraryMFD([rup.mag], [rup.mag_occ_rate])
          rcs = RuptureCollectionSource(
              source_id, src.name, src.tectonic_region_type, amfd, block)
          yield rcs